What is the focus of strain theory?

Strain theory, in sociology, proposal that pressure derived from social factors, such as lack of income or lack of quality education, drives individuals to commit crime. The ideas underlying strain theory were first advanced in the 1930s by American sociologist Robert K. Merton, whose work on the subject became especially influential in the 1950s. Other researchers set forth similar ideas, including American criminologist Albert Cohen and American sociologists Richard Cloward and Lloyd Ohlin

Srry but can you translate to english?